Evaluating the effects of direct-fed microbial supplementation on the performance, milk quality and fatty acid of mid-lactating dairy cows.

BACKGROUND: The objective of the experiment was to investigate the effect of a mixture of direct-fed microbial (DFM) on feed intake, nutrient digestibility, milk yield and composition, milk fatty acid and blood parameter in crossbred mid-lactating cows. METHODS: Twenty-four crossbred Holstein cows (body weight = 650±15 kg; days in milk = 100±20; daily milk yield = 25±3 kg) were used in a completely randomized design with three treatments: (1) CON, without DFM; (2) LS, inoculation with Lactobacillus fermentum (4.5 × 108 CFU/day) plus Saccharomyces cerevisiae (1.4×1010 CFU/day); and (3) LSM, inoculation with LS plus Megasphaera elsdenii (4.5 × 108 CFU/day). All animals received the same ration with 45.7% forage and 54.3% concentrate. RESULTS: Results showed that the highest feed intake was observed in treatments LS and LSM (p = 0.02). Compared with the CON, milk production, 4% fat-corrected milk, energy-corrected milk, fat (kg/day), protein (kg/day) and lactose (kg/day), FE and percent of fat were increased (p<0.05) by LSM, but unaffected by LS. Also, compared with the CON, both LS and LSM increased antioxidant activity (p<0.05). The concentration of C18:2c n-6 increased significantly in treatment LSM compared with the CON (p = 0.003). The concentration of C20:0 increased significantly in treatment LS compared with the CON (p = 0.004). The highest concentrations of insulin, glucose, triglyceride and cholesterol were observed by LSM (p<0.05). Compared with the CON, both LS and LSM increased blood monocyte, neutrophil, eosinophil and basophil (p<0.05), and blood lymphocyte was increased (p = 0.02) only by LSM. CONCLUSIONS: The results of the research showed that the use of DFMs had no effect on the digestibility, microbial load and the major part of fatty acids in milk. However, it improved feed intake, milk yield and antioxidant activity of milk and also increased the milk concentration of C18:2 n-6.

Effect of dietary Conocarpus erectus leaves and branches on milk yield, quality, antioxidant activity and fatty acid profile, and blood parameters of Najdi dairy goats.

To investigate the effect of Conocarpus erectus tree leaves and branches as a partial replacement of forage on milk yield and components, blood and rumen parameters of goats, 16 Najdi goats were used in a completely randomized design with 2 treatments (CON, without C. erectus; CE, contains C. erectus). The basic ratio consisted of 60% concentrate and 40% forage. In treatment CE, 22.5% of the forage (alfalfa hay and wheat straw) was replaced with C. erectus leaves and branches. The lowest amount of dry matter intake and digestibility were observed in the treatment CE (P < 0.05). The amount of milk production significantly increased (P = 0.01) in the treatment CE. The total count did not differ between treatments, but the highest amount of Lactobacillus spp. (P = 0.01) and the lowest amount of mold (P = 0.01) were observed in the treatment CE. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity decreased on days 15 (P = 0.02) and 31 (P = 0.01) of the experiment in treatment CE. The highest amount of short-, medium-, and long-chain fatty acids and also conjugated fatty acids were observed in the treatment CE (P < 0.05). Also, the concentration of fatty acids C16:0 and C18:0 was lower in the treatment CE (P < 0.05). The lowest amount of triglycerides, blood urea nitrogen, cholesterol, low-density lipoprotein, high-density lipoproteins, serum glutamic pyruvic transaminase, and serum glutamic oxaloacetic transaminase were observed in the treatment CE (P < 0.05). Ruminal pH and ammonia-N concentration were not affected by experimental treatment (P > 0.05). According to the results, the use of C. erectus leads to improved milk production and fatty acid profile, antioxidant activity, and microbial load.

The Effect of Three Levels of Concentrate and Grain Processing on Feeding Behavior, Nutrient Digestibility, Blood Metabolites and Fecal pH Of Turkmen Horses.

The aim of this study was to investigate, the effect of different levels of concentrates and grain processing on feeding behavior, nutrient digestibility, fecal pH and blood metabolites in the horse. Sixteen 5 to 11 years old Turkmen horses with an initial body weight 433±50 kg were used in this experiment based on completely randomized design. Four treatments were studied, in three treatments were used 20, 25 and 30% of concentrate containing processed grains (A20, A25 and A30, respectively), and in one treatment was used 25% of concentrate containing whole grain (B25). The amount of feed intake, chewing and swallowing rate and total intake for forage and concentrate were not affected by experimental treatments (P> .05). By increasing the concentrate level up to 30%, the digestibility coefficients of dry matter, organic matter, crude protein, ash-free neutral detergent fiber, ash-free acid detergent fiber and digestible energy increased. The highest digestibility coefficients were observed in A30 treatment (P< 0.05). The digestibility of organic matter, crude protein, ash-free neutral detergent fiber and digestible energy in A25 treatment significantly increased compared to B25 (P< 0.05). The concentration of total protein, triglycerides, cholesterol and low-density lipoprotein were not affected by experimental treatments (P> 0.05). The concentration of glucose increased with increasing concentrate for treatment A30 (P< 0.05). In conclusion, comparing the two levels of 25% concentrate showed that the use of processed grains compared to unprocessed grains had no effect on feeding behavior, fecal pH and blood parameters. The use of 30% concentrate containing processed grains improved digestion without adversely affecting feeding behavior and fecal pH.

The Positive Impact of Increasing Feeding Frequency on Feed Intake, Nutrient Digestibility, and Blood Metabolites of Turkmen Horses.

To determine the effects of feeding frequency on nutrient digestibility and blood metabolites in horse, 16 Turkmen horses were used with weight of 430 ± 46 kg and age of 7 ± 1.8 years. Four feeding frequencies with 2 (M2), 4 (M4), 6 (M6), and 8 (M8) meals per day were used for a period of 28 days. The ratio of hay to concentrate was 70:30 in the experimental diet. Acid insoluble ash was used as internal marker to determine digestibility. On the 27th day of experiment, the blood was collected on 13 time points throughout the day. The results of this experiment showed that feed intake was not affected by feeding frequency (P> .05). The highest amount of nutrient digestibility was observed in the M8 treatment compared to other treatments, and digestibility of nutrients was increased with increasing feeding frequency from M2 to M8. Also, serum cholesterol concentration was not influenced by the increasing feeding frequency (P= .451). But, diurnal mean concentration of blood metabolites including total protein concentration (P= .030), glucose (P= .014), triglyceride (P= .003), and low-density lipoprotein (P= .006) was statistically increased in treatment of 2 meals per day. In conclusion according to the results of present study, increasing the feeding frequency improved nutrient digestibility and blood metabolites in the treatment M8. However, associated with digestion coefficients and serum metabolites, there were no statistically difference between treatment M4 and M6.

Effect of microbial feed additives on growth performance, microbial protein synthesis, and rumen microbial population in growing lambs.

Arabi lambs (n =28; body weight = 24 ± 3.7 kg; average age = 120 ± 8 days) were used to investigate the effect of microbial additives on growth performance, microbial protein synthesis and rumen microbial population of fattening lamb based on completely randomized design. Four treatments were studied: (1) control (without additive; CON); (2) Lactobacillus fermentum and L. plantarum (FP); (3) Saccharomyces cerevisiae (SC) plus FP (SCFP); and (4) Megasphaera elsdenii plus SCFP (MSCFP). Lambs were inoculated before morning feeding (daily oral dosed) with a 50 mL microbial suspension as follows: FP, 50 mL bacterial suspension containing 4.5 × 108 colony-forming unit per day (cfu/d) of L. plantarum and L. fermentum (in ratio 50:50); SCFP, 50 mL microbial suspension containing 4.5 × 108 cfu/d FP and 1.4 × 1010 cfu/d SC; MSCFP, 50 mL microbial suspension containing 4.5 × 108 cfu/d Me, 4.5 × 108 cfu/d FP and 1.4 × 1010 cfu/d SC. Feed intake and body weight of lambs were not affected by microbial additives. Average daily gain and feed efficiency were increased on day 0 to 21. The highest concentration of uric acid, total excreted purine derivatives (PD), microbial N, microbial CP, and metabolizable protein were in MSCFP lambs. The ruminal population of Ruminococcus albus and Ruminococcus flavefaciens was higher in MSCFP and SCFP than CON and FP lambs. The highest and the lowest abundance of M. elsdenii and methanogen respectively was observed in lambs fed on microbial additives. The tendency to improve growth performance vs. CON may be due to improvements in microbial protein synthesis and microbial populations, especially fiber-degrading bacteria. The decrease in the population of methanogens as a result of the use of microbial additives is another positive result.